427 research outputs found
SESAME: Semantic Editing of Scenes by Adding, Manipulating or Erasing Objects
Recent advances in image generation gave rise to powerful tools for semantic
image editing. However, existing approaches can either operate on a single
image or require an abundance of additional information. They are not capable
of handling the complete set of editing operations, that is addition,
manipulation or removal of semantic concepts. To address these limitations, we
propose SESAME, a novel generator-discriminator pair for Semantic Editing of
Scenes by Adding, Manipulating or Erasing objects. In our setup, the user
provides the semantic labels of the areas to be edited and the generator
synthesizes the corresponding pixels. In contrast to previous methods that
employ a discriminator that trivially concatenates semantics and image as an
input, the SESAME discriminator is composed of two input streams that
independently process the image and its semantics, using the latter to
manipulate the results of the former. We evaluate our model on a diverse set of
datasets and report state-of-the-art performance on two tasks: (a) image
manipulation and (b) image generation conditioned on semantic labels
Citizen participation in news
The process of producing news has changed significantly due to the advent of the Web, which has enabled the increasing involvement of citizens in news production. This trend has been given many names, including participatory journalism, produsage, and crowd-sourced journalism, but these terms are ambiguous and have been applied inconsistently, making comparison of news systems difficult. In particular, it is problematic to distinguish the levels of citizen involvement, and therefore the extent to which news production has genuinely been opened up. In this paper we perform an analysis of 32 online news systems, comparing them in terms of how much power they give to citizens at each stage of the news production process. Our analysis reveals a diverse landscape of news systems and shows that they defy simplistic categorisation, but it also provides the means to compare different approaches in a systematic and meaningful way. We combine this with four case studies of individual stories to explore the ways that news stories can move and evolve across this landscape. Our conclusions are that online news systems are complex and interdependent, and that most do not involve citizens to the extent that the terms used to describe them imply
Tailored carrier/bacteria technology for rehabilitation of areas with pesticide-containing pollution – AQUAREHAB WP2
Postprint (published version
Epidemic processes in complex networks
In recent years the research community has accumulated overwhelming evidence
for the emergence of complex and heterogeneous connectivity patterns in a wide
range of biological and sociotechnical systems. The complex properties of
real-world networks have a profound impact on the behavior of equilibrium and
nonequilibrium phenomena occurring in various systems, and the study of
epidemic spreading is central to our understanding of the unfolding of
dynamical processes in complex networks. The theoretical analysis of epidemic
spreading in heterogeneous networks requires the development of novel
analytical frameworks, and it has produced results of conceptual and practical
relevance. A coherent and comprehensive review of the vast research activity
concerning epidemic processes is presented, detailing the successful
theoretical approaches as well as making their limits and assumptions clear.
Physicists, mathematicians, epidemiologists, computer, and social scientists
share a common interest in studying epidemic spreading and rely on similar
models for the description of the diffusion of pathogens, knowledge, and
innovation. For this reason, while focusing on the main results and the
paradigmatic models in infectious disease modeling, the major results
concerning generalized social contagion processes are also presented. Finally,
the research activity at the forefront in the study of epidemic spreading in
coevolving, coupled, and time-varying networks is reported.Comment: 62 pages, 15 figures, final versio
Inheritance patterns in citation networks reveal scientific memes
Memes are the cultural equivalent of genes that spread across human culture
by means of imitation. What makes a meme and what distinguishes it from other
forms of information, however, is still poorly understood. Our analysis of
memes in the scientific literature reveals that they are governed by a
surprisingly simple relationship between frequency of occurrence and the degree
to which they propagate along the citation graph. We propose a simple
formalization of this pattern and we validate it with data from close to 50
million publication records from the Web of Science, PubMed Central, and the
American Physical Society. Evaluations relying on human annotators, citation
network randomizations, and comparisons with several alternative approaches
confirm that our formula is accurate and effective, without a dependence on
linguistic or ontological knowledge and without the application of arbitrary
thresholds or filters.Comment: 8 two-column pages, 5 figures; accepted for publication in Physical
Review
Original Contribution Do Psychosocial Stress and Social Disadvantage Modify the Association Between Air Pollution and Blood Pressure? The Multi-Ethnic Study of Atherosclerosis
Researchers have theorized that social and psychosocial factors increase vulnerability to the deleterious health effects of environmental hazards. We used baseline examination data (2000)(2001)(2002) from the Multi-Ethnic Study of Atherosclerosis. Participants were 45-84 years of age and free of clinical cardiovascular disease at enrollment (n = 6814). The modifying role of social and psychosocial factors on the association between exposure to air pollution comprising particulate matter less than 2.5 µm in aerodynamic diameter (PM 2.5 ) and blood pressure measures were examined using linear regression models. There was no evidence of synergistic effects of higher PM 2.5 and adverse social/psychosocial factors on blood pressure. In contrast, there was weak evidence of stronger associations of PM 2.5 with blood pressure in higher socioeconomic status groups. For example, those in the 10th percentile of the income distribution (i.e., low income) showed no association between PM 2.5 and diastolic blood pressure (b = −0.41 mmHg; 95% confidence interval: −1.40, 0.61), whereas those in the 90th percentile of the income distribution (i.e., high income) showed a 1.52-mmHg increase in diastolic blood pressure for each 10-µg/m 3 increase in PM 2.5 (95% confidence interval: 0.22, 2.83). Our results are not consistent with the hypothesis that there are stronger associations between PM 2.5 exposures and blood pressure in persons of lower socioeconomic status or those with greater psychosocial adversity. air pollution; blood pressure; population groups; social environment; social medicine; social psychology Abbreviations: CVD, cardiovascular disease; DBP, diastolic blood pressure; ETS, exposure to second-hand smoke; MAP, mean arterial pressure; MESA, Multi-Ethnic Study of Atherosclerosis; PM 2.5 , particulate matter less than 2.5 µm in aerodynamic diameter; PP, pulse pressure; SBP, systolic blood pressure; SES, socioeconomic status
Exposure to traffic and left ventricular mass and function: the Multi-Ethnic Study of Atherosclerosis.
RATIONALE: Ambient air pollution has been associated with heart failure morbidity and mortality. The mechanisms responsible for these associations are unknown but may include the effects of traffic-related pollutants on vascular or autonomic function.
OBJECTIVES: We assessed the cross-sectional relation between long-term air pollution, traffic exposures, and important end-organ measures of alterations in cardiac function-left ventricular mass index (LVMI) and ejection fraction-in the Multi-Ethnic Study of Atherosclerosis, a multicenter study of adults without previous clinical cardiovascular disease.
METHODS: A total of 3,827 eligible participants (aged 45-84 yr) underwent cardiac magnetic resonance imaging between 2000 and 2002. We estimated air pollution exposures using residential proximity to major roadways and interpolated concentrations of fine particulate matter (less than 2.5 microns in diameter). We examined adjusted associations between these exposures and left ventricular mass and function.
MEASUREMENTS AND MAIN RESULTS: Relative to participants living more than 150 m from a major roadway, participants living within 50 m of a major roadway showed an adjusted 1.4 g/m(2) (95% CI, 0.3-2.5) higher LVMI, a difference in mass corresponding to a 5.6 mm Hg greater systolic blood pressure. Ejection fraction was not associated with proximity to major roadways. Limited variability in estimates of fine particulate matter was observed within cities, and no associations with particulate matter were found for either outcome after adjustment for center.
CONCLUSIONS: Living in close proximity to major roadways is associated with higher LVMI, suggesting chronic vascular end-organ damage from a traffic-related environmental exposure. Air pollutants or another component of roadway proximity, such as noise, could be responsible.http://deepblue.lib.umich.edu/bitstream/2027.42/78524/1/VanHeeAdar2009_AmJRespirCritCareMed.pd
Embellishing Text Search Queries to Protect User Privacy
Users of text search engines are increasingly wary that their activities may disclose confidential information about their business or personal profiles. It would be desirable for a search engine to perform document retrieval for users while protecting their intent. In this paper, we identify the privacy risks arising from semantically related search terms within a query, and from recurring highspecificity query terms in a search session. To counter the risks, we propose a solution for a similarity text retrieval system to offer anonymity and plausible deniability for the query terms, and hence the user intent, without degrading the system’s precision-recall performance. The solution comprises a mechanism that embellishes each user query with decoy terms that exhibit similar specificity spread as the genuine terms, but point to plausible alternative topics. We also provide an accompanying retrieval scheme that enables the search engine to compute the encrypted document relevance scores from only the genuine search terms, yet remain oblivious to their distinction from the decoys. Empirical evaluation results are presented to substantiate the effectiveness of our solution. 1
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